lab: introduction to mcidas-v (mcv) basic functionalities

LAB: Introduction to McIDAS-V (McV)

This lab shows some of the basic functionalities of McV, including opening files, displaying different channels,

changing projection, etc. At the same time, we will briefly analyze a convective cloud system over South Africa

/ Botswana with Meteosat -8 (MSG) SEVIRI and Meteosat-5 MVIRI data.

The actual official version of McV is currently version 1.8. You should download it from the McV web

page: https://www.ssec.wisc.edu/mcidas/software/v/download/ and install on your computer. With version

1.8 you can display GOES-16 ABI data, together with all other data necessary for the labs.

In McV you have different ways of opening satellite data, like local or remote ADDE servers, so-called

bundles or simply opening a file with Hydra (Hydra is integral part of McV). In this lab, we will open the data

by using local ADDE servers, just like you would do on a Eumetcast receiving station (where the MSG data is

locally available in HRIT format).

Here are step-by-step instructions for this lab (key questions are in yellow):

1. Start McIDAS-V

a. Open McIDAS-V by double-clicking on the runMcV.bat file in the McIDAS-V-System directory

(or the McV icon, if created on the Desktop).

The opening of McV may take a bit longer (depends on PC power). Two windows will open: the McIDAS-V

map window (display window) and the Data Explorer window (data and channel selection window).

2. Set local ADDE servers

a. In the McIDAS-V map window, select Tools → Manage ADDE datasets

b. Select the Local Data tab

c. Select the MSG Dataset (with a new installation the table will be empty so you will have to enter all

Datasets)

d. Click Add New Dataset

e. Fill in the required input as per table below. You can always change the input to created ‘servers’ by

clicking on Edit Dataset.

https://www.ssec.wisc.edu/mcidas/software/v/download/

f. Click Save Changes

g. Click OK when you are done.

3. Open MSG SEVIRI IR10.8 image (SEVIRI channel 9)

a. In the Data Explorer window, select the Data Sources tab

b. Select Imagery under Satellite in the panel on the left side

c. Select Server: <LOCAL-DATA>

d. Select the Dataset: MSG

e. Click Connect and wait

f. Select the Image Type: Channels 1-11

g. Go to the Absolute tab and select the image at 2005-11-06 14:00:00 UTC

h. Click Add Source

i. In the Field selector tab, select Channels 1-11 in the Data Sources panel and then 10.8 um IR

Surface/Cloud-top Temp → Temperature under the Fields panel and wait (Note: for IR images,

we always select Temperature. Raw is to display the original counts (0 to 1023) and Radiances

would display the radiance data (converting the counts with calibration info to radiances).

j. Select Imagery → Image Display in the Displays panel

k. Select the Advanced tab and put the Magnification slider to the maximum (1)

l. Go to the Region tab and select a large area, from pole to pole, roughly to encompass both Europe

and Africa. You can do this by holding down the Shift key and dragging the area with the left

mouse button. You can also zoom in by using the mouse wheel.

m. Click Create Display, wait

n. Change the range of the displayed IR image: right-click the colour bar and select Change Range.

Change the range from 190 to 300 K and click OK.

o. Zoom in on South Africa (right mouse button to drag, mouse wheel to zoom in)

p. Check the result: look at the IR image in the McIDAS-V window. The inverted IR image should be

displayed as in the image below. Check the info given in the McIDAS-V window.

q. Tick on and off the background layer to switch the map on and off

4. Change the projection and enhance the IR image

a. The current projection is the simple equidistant Lat/Lon projection (Plate Carrée), which is the best

choice if you want to export the images to Google Earth. Change the projection of the image to the

original (MSG) satellite projection by selecting Projections → From Displays → Image (MSGT)

Projection from: Image Display

b. Now the IR image should be a rectangular image (as defined by the lines and columns of the

original MSG image).

c. Change the projection to different ones by selecting Projections → Predefined → …

d. As the image zooms out automatically, strongly zoom in on the convective clouds over South Africa

e. Now, change the range of the displayed IR image to 190 to 210 K, to only see the coldest clouds.

The image should look like this:

f. Now, find the coldest IR pixel in the image: hold down the middle mouse button (the wheel).

g. A white cross appears at the cursor position, and the lat/lon and BT information appears on the

bottom of the display window, as in the image below. Note that in order to see the readings, the

window should not be full screen.

h. Move the cursor across the image and find the coldest pixel of the SEVIRI IR image. Note the value.

Is it below 190 K?

i. Let us put a colour bar on the IR image

j. Left-click on the layer name (Channels 1-11 (All Bands)) in the Legend panel.

k. The Layer Controls tab in the Data Explorer window pops up. See the image below:

l. Click on the info button, as indicated in the image

m. A new window with different tabs will pop up as shown below

n. In the Colour Scale tab make the colour table visible and change the font as indicated above

o. Click Apply and when you like the result click OK. The image should look like this (with the

colour bar on top):

p. Now let us change the range back to 190 to 300 K and create a colour enhancement of the IR image

q. Right-click the colour bar and select Change Range. Change the range from 190 to 300 K and click

OK. r. Right-click again the colour bar and select System → Legacy → Setvak (see Annex 1 for info

about this colour table)

s. Zoom out to see South Africa and Botswana; the image should look like this:

t. Finally, save the image. To do so, go to the McIDAS-V window and navigate to View → Capture

→ Image (see the image below)

u. Save the image on your local system (where you find suitable) in the directory “Images” with

filename:20051106_1400_msg_ir108_col.png

(please, you must type .png as the extension of the file to get PNG images!)

v. Click Save

Question: conceptually, what feature are the cold storms over northern South Africa and southern Botswana?

Can you see any structures? What do you think is the suitable temperature range for the global view?

Note: To answer these questions, you may display the VIS0.8 and WV6.2 images. And, you could display the

Airmass RGB (AIRM), Dust RGB (DUST) and the Severe Convection RGB (SCON). In the next Labs you will

learn how to display RGB images.

5. Display the SEVIRI HRV Image and compare to IR10.8 image




d. Select the Dataset: MSGHRV


f. Select the Image Type: HRV Channel


h. Click Add Source and wait

i. In the Field selector tab, select 0.7 um Broadband visible → Reflectivity under the Fields panel

and wait


k. Select the Advanced tab and put the Magnification slider to the maximum

l. Go to the Region tab and select a large area from Namibia to Madagascar


Check the result: the HRV image should be displayed on top, but it is relatively dark. Question: Why is it so

dark?

n. Change the range of the displayed HRV image: right-click on the colour bar → Change Range,

from 0 to 60 (% reflectance). The image becomes much brighter!

Zoom on the convective storms and toggle the HRV and the IR images to compare the images. What extra

features do you see in the HRV image that you cannot see in the IR image (see e.g. image below)?

o. Now, zoom to Madagascar and you can see that the HRV image is cut off as shown in the image

below. Why is the image black east of the red line (think of the time of the image 14 UTC)?

p. Save the HRV image: in the main window, navigate to View → Capture → Image and save the

image

q. Click Save

6. Display Met-5 infrared image (for comparison)




d. Select the Dataset: IODC


f. Select the Image Type: MVIRI


h. Click Add Source and wait

i. In the Field selector tab, select 11.5 um IR Surface/Cloud-top Temp → Temperature under the

Fields panel and wait


k. Select the Advanced tab and put the Magnification slider to the maximum

l. Go to the Region tab and select the region that includes South Africa and Madagascar


n. Go to the McIDAS-V window to see the result

o. Change the range of both IR images (Met-5 MVIRI and Met-8 SEVIRI) to 190 to 300 K and use

the Setvak colour table for both images.

Zoom on the convective storms over northern South Africa. Toggle the Met-5 (MVIRI) and the Met-8

(SEVIRI) IR images. As you can see, the (cold) clouds are not in the same position. Question: why?

Compare the IR brightness temperatures of the two IR images. Hold down the mouse wheel and read the values.

Are they the same? Which are higher?

p. Now, remove the Met-5 MVIRI IR image by clicking on the remove button as indicated below

q. And last but not least, change the background map a bit

r. Click on the text of the Default Background Maps label

s. That will open the Layer Controls tab in the Data Explorer window

t. In the Maps tab, tick off World Coastlines and World Country Outlines and tick only the World

Country Outlines on the bottom of the list and select cyan as colour. This map database has also

some islands included!

u. In the Lat/lon tab, create a lat/lon grid of 5 degrees interval (change the Interval for both Latitude

and Longitude to 5). Press Enter in order to approve the changes. The result should look like this:

v. Save the IR image: in the main window, navigate to View → Capture → Image and save the image

w. Click Save

7. Display Met-5 and Met-8 infrared images on 3D Globe

a. In the McIDAS-V window, select File → New Display Window → Globe Display → One Panel

b. A new McIDAS-V window will appear, see example below

c. Go to the Data Explorer window and load the Met-8 (MSG) IR10.8 image for the same time at full

resolution for the whole Met-8 disk (if you do not remember how to do that, see instructions above)

d. Rotate the Globe to see Africa (hold Control key and use right mouse button)

e. Set the range again to 190 to 300 K

f. Load the Met-5 IR image (full disk) and set the range also to 190 to 300 K. The display should look

like this:

g. The Met-5 image is on top of the Met-8 image. You can change this order by: right-click on the

label of the Met-8 image and select View → Bring to Front

h. Rotate the Globe and zoom as you like. How far east does Met-5 cover (where is the nadir point)?

Is Beijing included in the image?

i. You can create an animated rotation of the Globe by holding the Control key and swiping the right

mouse button across the image (like you do on tablet PCs with your finger)

Read more about this case on the web:

Severe weather over South Africa and Botswana

http://www.eumetsat.int/website/home/Images/ImageLibrary/DAT_IL_05_11_06.html

Annex 1: How to create the Setvak IR colour table

For info, check the Convection Working Group website.

a. Open an IR image and set range from 200 to 300 K

b. Right-click on the colour bar of the IR image, select Edit Colour Table

c. A new window (Colour Table Editor) will pop up

d. Top Menu: select Color Tables → System → Inverse Grey Scale

e. Add 5 new breakpoints in the colour table by right-clicking on the colour bar Add Breakpoint →

At Data Point → Value = 208, Click OK

f. Repeat this for breakpoints at 216, 224, 232 and 240 K.

g. Lock all breakpoints: right-click on the breakpoint → Lock Breakpoint. This is to prevent you from

moving/changing the breakpoints. The Colour Table Editor should look like this:

h. Then, select breakpoint 200 K (left-click)

i. Select the colour for this breakpoint by clicking on the RGB tab

j. Select Red=131, Green=0, Blue=0 (dark red), see screenshot below:

http://essl.org/cwg/?page_id=157

k. Do the same for the breakpoint 208 K (255,0,0) red

l. Do the same for the breakpoint 216 K (255,255,0) yellow

m. Do the same for the breakpoint 224 K (0,255,255) cyan

n. Do the same for the breakpoint 232 K (0,0,255) blue

o. Do the same for the breakpoint 240 K (0,0,131) dark blue

p. You should now see some nicely coloured lines in the colour bar window (see below)

q. Now, to interpolate between these breakpoint colours, you have to:

i. Right-click on the 208 K breakpoint, and select from the drop down list: Edit Colours →

Interpolate → Left

ii. Do the same for the 216 K, 224 K, 232 K and 240 K breakpoints

r. Now, let us also enhance the warm part of the colour table (240 to 300 K) by selecting the 240 K

breakpoint again (left-click)

s. Change the colour to white (RGB 255,255,255)

t. Right-click on the 300 K breakpoint, and select from the drop down list: Edit Colours →

Interpolate → Left. The colour bar should look like this:

u. Save the new colour table: Colour Table Editor window: File → Save As → Select name

lab: introduction to mcidas-v (mcv) basic functionalities

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